NOTE: These are the main UFC 2009 Undisputed cheats that are usually applied by pressing down the right key combination. Please find the instructions on how to use these cheats below.

Unlock SkyScrape from Tapout
At the title screen, press [Up], [Up], [Up], [Down], [Left], [Right], [Up], [Start]. SkySkrape is a middleweight with an overall rating of 74.

Hints

NOTE: As their name suggests hints are not exactly UFC 2009 Undisputed cheats, and are usually just simple (but very useful) tips on how you can unlock secret level, features, find hidden areas and such. Hopefully these will make playing UFC 2009 Undisputed even more entertaining.

Black Belt (Gold): Win 100 online Ranked Matches with a CAF or UFC fighter.
Blue Belt (Bronze): Win 15 online Ranked Matches with a CAF or UFC fighter.
Brown Belt (Silver): Win 50 online Ranked Matches with a CAF or UFC fighter.
Call me "No Touch!" (Gold): Complete Career Mode and retire undefeated.
Gold Digger! (Silver): Obtain all the gold medals in a Weekly Mission for Online Mode.
Hall of Famer (Silver): Enter the Hall of Fame with a fighter during Career Mode.
Ooh, in ya face! (Silver): Win a fight by flash KO in a Ranked Match with a CAF or UFC fighter.
Original fighter (Silver): Create A Fighter and use the CAF in Exhibition or Online Mode.
Papa Said Knock You Out! (Silver): Win 15 online Ranked Matches with a CAF or UFC fighter by KO.
Platinum: Obtain all Gold, Silver, and Bronze Trophies!
Pound-for-Pound Champion (Gold): Win the UFC Championship in each weight class in Career Mode.
Purple Belt (Silver): Win 30 online Ranked Matches with a CAF or UFC fighter.
Red Belt (Gold): Reach level 50 or higher in Online Mode.
Roster Run-through (Silver): Complete one fight in Exhibition Mode with each UFC fighter.
Student of the game. (Silver): Complete all tasks from the Tutorial Mode.
That was easy! (Bronze): Win in under 20 seconds of the 1st round against a COM UFC Fighter in Exhibition or Career Mode.
Trophy Collector (Silver): Obtain all the trophies in Career Mode with a fighter.
Two of my favorites! (Bronze): Watch the Octagon Girl cutscene 15 times without skipping it.
UFC Historian (Silver): Unlock all movies from the Classic Fights Mode.
Ultimate Highlights (Bronze): Dominate the opponent in all 3 scenes of a replay segment.
Ultimate Knockout (Bronze): From the gassed state, KO an opponent in any mode.
Ultimate Submission (Bronze): From the gassed state, Submit an opponent in any mode.
Undisputed Champion (Silver): Win the UFC Championship with a fighter in Career Mode.
Wanted: Flying Mouthpieces (Bronze): Mouth piece travels more than 3 meters when knocked out.
Wax Off! (Bronze): Escape 20 submissions by technical escape against a COM UFC Fighter in Exhibition or Career Mode.
Wax On! (Silver): Win 15 online Ranked Matches with a CAF or UFC fighter by submission.
Where's my bonus check? (Bronze): Obtain the KO, Submission and Fight of the Night Awards with a fighter in Career Mode.
White Belt (Bronze): Win an online Ranked Match with a CAF or UFC fighter.
World Class Grappler (Silver): Win by Submission using no striking moves against a COM UFC Fighter in Exhibition or Career Mode.
World Class Striker (Silver): Win by KO without using any grappling moves against a COM UFC Fighter Exhibition or Career Mode.
You really like me! (Silver): Gain a million or more fans in Online Mode.

Unlock MASK as LHW fighter.
Succeed 3 submissions in a row in career mode.

Unlock 'Punkass' as playable character
To unlock the TapOut crew member Punkass as a fighter, obtain a Sponsorship from TapOut during career mode.

Unlock Dana White
To unlock UFC President Dana White as a fighter, the game requires you do the following. You must submit: Frank Mir George St. Pierre Demian Maia BJ Penn And knockout: Quinton Jackson Anderson Silva Brock Lesnar Kenny Florian It doesn't matter if it's with a created or UFC in-game character. Once you've beaten the last fighter, the game will pop-up to advise you.

Openweight Mode: To unlock openweight mode, where any fighter can fight in any weightclass. You must beat every fighter in their respective weightclass with the lowest

Create a Fighter Exploit
From Create A Fighter 1. Load fighter 2. Select fighter (press X) 3. Toggle stats on (press square) 4. Toggle stats off (press square) 5. Select fighter (press X) 6. Select customize fighter (press X) 7. Select fighter style/attributes (press X) 8. Select fighter skills (press X) 9. Now you have 3024 points to use to raise the skill level of your fighter 10. When you reach zero points (press X) to accept 11. Back out one screen (press O) and chose finish. 12. Repeat note: For this to work you must have a fighter to load. What I did was take the default guy and save him. Tip: After you make your super fighter save and copy him so you only have to do this exploit once. After that you can change all his attributes later.